PHYTOTOXICITY STUDIES WITH LACTUCA SATIVA IN SOIL AND NUTRIENT SOLUTION

Abstract

The toxicity of 76 priority pollutants to lettuce (Lactuca sativa) was determined in soil and in nutrient solution. In the first case a statie and in the latter a semistatic exposure was estab lished. Volatile and easily degradable compounds had high EC50 values in soil (> 1,000 g/g). In nutrient solution, however, several of these compounds were rather toxic. Quantitative structure activity relationships (QSARs) relating EC50 values to log Ka could be described for the toxicity in nutrient solution. Generally, the toxicity of the compounds increased with increasing lipophilic ity. Deviations were (partly) caused by reactivity (N-containing compounds, double bonds in com pounds), low lipophilicity (log K values